diff --git a/src/muz/rel/dl_base.h b/src/muz/rel/dl_base.h
index 2dffa04f6..c14977c04 100644
--- a/src/muz/rel/dl_base.h
+++ b/src/muz/rel/dl_base.h
@@ -470,7 +470,7 @@ namespace datalog {
                \brief fast emptiness check. This may be partial.
                The requirement is that if fast_empty returns true 
                then the table or relation is in fact empty.
-               It is allowed to return false even if the relation is non-empty.
+               It is allowed to return false even if the relation is empty.
             */
             virtual bool fast_empty() const { return empty(); }